The home team led 1-0 at half-time but Dedebit scored 3 second-half goals with 2 goals coming from star player Dawit Fekadu (50′ & 58′).
It was a sweet victory for Dedebit, which saw 4 of its international players sent back to Ethiopia after they were denied entry in the country because of visa problems and irregularities. The four players, which included Ghanaian trio Gabriel Ahmed, Adamo Mohammed, Sulemana Abubakari and the Nigerian Samuel Sanumi, flew back after their visa issues were resolved.
Sanumi actually scored the third and decisive goal for Dedebit.
The two teams will play their return leg match in Addis Ababa in 2-week time.
St. George will take on MC El Eulma of Algeria in CAF Champions League match later on today.